As shown in FIG. 1, a prior art spray nozzle consists of a nozzle holder 10 and a nozzle head 11 which are engaged with each other. At the top of the nozzle holder 10 near to the water outlet 12 is formed an external thread 13, whereas inside of the nozzle head 11 is formed an internal thread. While changing or installing the nozzle head 11, the user will need to spend more time in swiveling between the nozzle head 11 and the nozzle holder 10 so as to engage with the water outlet 12.
Such a design is defective in that it is waste of time and needs to change the shapes of the nozzle head if the spray nozzle is required to have different forms and ranges in spraying.